Code 61

[John Boothby]

I have replaced my entire secondary vac system including all actuators, solenoids and check valves. I get the "Service Engine Soon" light even though the secondary parameters are not met, ie: rpm 3K and throttle to the floor. The temps are up though. I can be cruising at 65-70mph 2k rpm and if I hit a small grade and slightly increase the throttle, (below 3k) I will get the light. About a month after I replaced all the secondary components I got this light and traced it back using the FSM to the secondary solenoid under the front of the plenum. I replaced it and all was well until now. I am getting tired of r&r ing the plenum. Could it be a MAP sensor? I have a DRM chip, type unknown. I have checked the plumbing with a hand vac and all checks ok. I am getting frustrated!!

[GOLDCYLON]

John last time I had this the secondary actuator rod was cracked at one of the screw points. The rod had actually failed. Did you remove your actuators when you hand pumped them. Are they pulling off to one side or straight as they should be ?

[John Boothby]

I did not remove them when I vac tested them, but they are new. They worked though. The starboard side actuator is a little stiffer than the portside. They look like they are pulling straight, but I do not know how to tell if one is reversed?

[rhipsher]

If you replaced the secondary vacum solenoid and everything was fine but not now then it's entirely possible that it could have gone bad. There's no way to know how many years it sat on a shelf before you got it. There is a ZR-1 member on the other forum who also lives in Sin City that I sold an actuator to that has done quit a bit of his own work on his. What I would suggest is you two get together and swap your vacum solinoid with his and see if there is any difference. It wouldn't be the first time sombody got an NOS part and it was bad. Let me know and I'll give you his contact info.

[GOLDCYLON]

I did not remove them when I vac tested them, but they are new. They worked though. The starboard side actuator is a little stiffer than the portside. They look like they are pulling straight, but I do not know how to tell if one is reversed?

Unfortunately these have a high failure rate new right out of the box (ask me how I know) My problem was the port throttle rod that the black pieces connect too. The SES light always came on with Accel and then went away after my foot came of the throttle. Check the long linkage rods in there (Both sides)

[John Boothby]

If you replaced the secondary vacum solenoid and everything was fine but not now then it's entirely possible that it could have gone bad. There's no way to know how many years it sat on a shelf before you got it. There is a ZR-1 member on the other forum who also lives in Sin City that I sold an actuator to that has done quit a bit of his own work on his. What I would suggest is you two get together and swap your vacum solinoid with his and see if there is any difference. It wouldn't be the first time sombody got an NOS part and it was bad. Let me know and I'll give you his contact info.

Give me his contact info. I don't use the other forum.

This vacuum canister is on a 91' Z.

http://www.zr1.net/forum/showthread.php?p=83330#post83330

It's a 90. Not the canister, the actuators.

Thanks for the replies.

[John Boothby]

Jerry, get the gaskets ready, looks like another plenum pull!!

[A26B]

John,

Just saw Code 61 is the title of the thread...... duh.

Do you have the service manual to follow the diagnostic flow chart?

[John Boothby]

I use a Tech-1A. Code 61 is the only code showing. I have cleared the code using the Tech-1A. The thing I am trying to understand, is that the SES light will come on and throw a code 61 even though the parameters have not been met to initiate the secondaries. I have used the FSM to diagnose the problem before and it was the secondary solinoid. I replaced it with a new one from White Racing and everything was ok for awhile, but now I get the SES light again. I guess I am just trying to avoid another plenum pull.

[A26B]

John,

Quote from the Service manual:
"During NORMAL engine power operation, (secondary operation disabled) a DTC 61 will set if any vacuum is present at the air inlet valve actuators. When DTC 61 is set, engine speed is limited to 3,000 RPM."

I haven't taken the time to try & review all the diagnostics to see what else besides the solenoind valve, might be involved (secondary vacuum sensor, etc.) Just thought I would tell you what I found regarding a DTC 61 in normal conditions, i.e. no full power operation.

Hope this helps a little bit.

[John Boothby]

It does not set a code when secondaries are disabled. Only when the power key is on "Full Power". Also, the rpm is not limited. It also seems like I am getting full power, so I am thinking "sensor" as in MAP. I have two new MAP sensors (behind plenum and under brake vac can). I will try them and see what happens before removing the plenum again.

Thanks again for the replies. Any more suggestions, let me know.

[A1990]

According to Marc's presentation at the Gathering this year, when in Full Power mode, 35% throttle at 2000rpm's will open the secondaries on a 90-92 model. Once open they will remain open until throttle is under 5%.

[John Boothby]

That sounds more like whats happening. Do the secondary injectors still function if the secondary intake valves do not open up? Does the "Instant Milage" number change when the secondaries come on? Common sense says yes. But..........

[A1990]

Go here http://www.zr1specialist.com/HAT%20Web/presentations/Presentations%20Page.htm (http://www.zr1specialist.com/HAT%20Web/presentations/Presentations%20Page.htm)
and read the 2010 presentation about secondaries. I believe it says that the injectors fire before the secondary ports open by .3 seconds.

[John Boothby]

Thanks Dennis.

[rhipsher]

John I still havent heard back from the guy that lives in your area. Still waiting.